Stabilization of animal and vegetable fats and oils



Patented Jan. 4, 1938 STABIIJZA'I'lbN OF ANIMAL AND VEGE- TABLE FATSAND OILS G orge H. Latham, Wilmington, DeL, assignor to E. 1. du Pont de Nemonrs & Company, Wilmington, DeL, a corporation of Delaware No "Drawing.

Application November 6, 1935, Serial No. 48,496

10 Claim (01. 87-12) This invention relates to the'stabilization of animal and vegetable fats andoils and, more particularly to the inhibition of the development of rancidity therein. 4 v 6 Many compounds are known'which will vprevent the development 01' rancidityin animal and vegetable fats and oils but practically all or them are unsuitable because they are either toxic and therefore cannot be used forstabilizing the edible 10 oils and fats, or else they impart bad odor and taste to such fats and oils. .Some of these compounds are so volatile, that they are removed from the tats and oils during cooking or in deepfat frying operations, while others are-relatively l insoluble in the fats and oils.

An object of the present invention is to pro- 25 to provide new compositions of matter and to advance the art. Other objects will appear hereinafter. I These objects may be accomplished in accordance with my invention which comprises incor- 30 porating, in animal and vegetable fats and oils normally tending to become rancid, a. small amount, sufficient to inhibit rancidity development therein, of a phenol having at least one 'alkoxy group in at least one of the positions 5 ortho and para to .a phenolic hydroxyl' group and at least one hydroxy aliphatic group in which at least one carbon atom of which is directly bonded to a carbon atom of the aromatic ring, said phenol consisting of carbon, hydrogen and oxygen.

droxyl, alkoigy, or aliphatic groups besides those above specified. The oils and fats so treated are much more resistant to rancidity development than are untreated oils and fats. 1

A By the phrase said phenol consisting oi'carbon, hydrogen and oxygen", I mean that the complete compound consists of carbon, hydrogen an oxygen, and isdevoid of other elements.

While the broad class of compounds mentioned 50 hereinbeiore will, in general, be eflectivetor my purposes, I prefer the mononuclear phenols al- 55 have found to be particularly satisfactory for my purppse'are vanillyl alcohol and coniferyl alcohol. The oils and fats which I propose to stabilizeare animal and vegetable in origin and are glycerides of the'more or less unsaturated higher fatty acids mixed, of course, with some saturated 5 glycerldes. Amongst the fats and oils which may be stabilized are linseed oil, China-Wood oil, cod liver oil, or the highly unsaturated glycerides which, for the most part, compose them. In general, this invention is particularly directed to the stabilization of those fats and oils-whichhave iodine numbers below 120, examples of which are castor oil, olive oil, rapeseed oil, coconut oil, palm oil, corn oil, sesame oil, peanut oil, neats foot oil, butter fat, lard, beet tallow, and hydro i5 genated oils and fats such as are sold under the trade names of Crisco and Snowdrift. I do not wish to be limited to the use of my compounds in the raw oils and fats, since, for certain uses, the oil or fat may be previously subjected to various treatments, such as blowing with air at more or less elevated temperatures or to simple heat treatments. My compounds and the edible oils and fats containing them can furthermore be used 'as ingredients in the preparation of pastries and other bakery products, potato chips, mayonnaise, salad oils, and the like. They may be used alone or in combination with other materials as textile dressings, lubrica'nts'and the like. However, my compounds are particularly adapted for use in edible and medicinal oils and fats and in food products in which such oils and fats are ingredients. The concentration in which my agents may be used will vary with the kind of oil or fat to be stabilized, the degree of stabilization desired, the particular agent and other considerations depending upon the desire of the user. The compounds will, in general, be used in concentrations of from about 0.001% to about 1.0% based on the 40 oil or fat to be stabilized,

into effect and the advantageous results to'be following examples are obtained thereby, the

given:

F Ezamplel A portion of refined cottonseed oil was divided into two parts. One part was retained asa blank a or control and to the other was added one per .atent of vanillyl alcohol. Pieces of filter paper of standard size and type were saturated with the two portions of oil, blotted to remove excess oil, stored in stoppered bottles at 65 and (in duplicate experiments) at room temperature, and examined daily for rancid odor, discoloration,

Ezcample 2 Refined cottonseed oil containing one per cent of coniferyl alcoholwas tested as in Example 1. Results were as follows:

Discoloration days for rancidity to develop Agent (1% concentration) Produced 65 0. Room temperature None (untreated oil) None. l 13 Coniferyl alcohol ---do..-.- 2 26 Coniferyl alcohol has no appreciable odor or taste, and does not discolor oils or fats.

Example 3 One per cent of vanillyl alcohol was incorporated into a portion of melted lard by stirring and the treated lard, together with an untreated portion thereof, heated in air with frequent stirring for one hour at 200 C. Potato chips were fried under the same conditions in each portion, drained of excess lard, stored in stoppered bottles at 65 and tested daily for rancidity development. The two portions of lard were then heated 11 hours longer under the same conditions, and another series of potato chips was tried and tested in the same manner. Results were as follows:

Days for rancidity development of potato chips fried after lard was heated number Agent (1% concentration) oi hours indicated 1 hour 12 hour None (untreated lard) 8 l3 Vanillyl alcohol 27 26 Methylol-hydroquinone monomethyl ether. Methylol hydroquinone monododecyl ether. I 4-methylol-2-dodecoxy phenol (dodecyl analog of vanillyl alcohol).

2,6-dimethoxy-4-methylol phenol. 2-methylol-6-decoxy phenol. 2-methylol-4-undecoxy phenol.

Mixtures of two or more of my agents may also be employed in any of the oils or fats hereinbefore mentioned or in mixtures of such oils and fats or compositions containing them. Ethers of the alcohols hereinbefore disclosed may also be ated in foods.

used in some cases, and as an example of an ether of the class, divanillyl ether may be mentioned.

It is a characteristic of the compounds covered by this invention that they cause little or no discolorationor objectionable odor or taste in the animal and vegetable fats and oils. This feature of my compounds is especially important with respect to the edible fats and oils because objectionable taste, odor or color cannot be toler- The low volatility of certain of my compounds is a particularly valuable feature which makes for permanence in the oil or fat, even when such fat or oil is subjected to heating as in cooking or deep-fat frying operations. A third distinct advantage of my compounds is that they are for the most part substantially insoluble in water but soluble in the oils or fats which I wish to stabilize, so that they will not be removed from such oils and fats in cooking operations in which they come into more or less contact with Water. Furthermore, their stabilizing properties are not destroyed by heat in cooking and deep fat frying operations.

While I have disclosed the preferred embodiments of my invention and the preferred modes of carrying the same into effect, many variations and modifications may be made therein and will be apparent to those skilledin the art. ingly, the scope of my invention is to be limited solely by the appended claims construed as broadly as is permissible in view of the prior art.

I claim: I

1. Animal and vegetable fats and oils normally tending to become rancid having incorporated therein, in an amount suificient to inhibit rancidity development, a phenol having at least one alkoxy group in at least one of the positions ortho and para to a phenolic hydroxyl group and at least one hydroxy aliphatic group in which at least one carbon atom is directly bonded to a carbon atom of the aromatic ring, said phenol consisting of carbon, hydrogen and oxygen.

2. Animal and vegetable fats and'oils normally tending to become rancid having incorporated therein, in an amount sufllcient to inhibit rancidity development, a phenol oi the benzene series having at least one alkoxy group in at least one of the positions ortho and para to a phenolic hydroxyl group and at least one hydroxy aliphatic group in which at least one carbon atom is directly bonded to a carbon atom of the arcmatic ring, said phenol consisting of carbon, hydrogen and oxygen.

3. Animal and vegetable fats and oils normally tending to become rancid having incorporated therein, in an amount sufiicient to inhibit rancidity development, a monohydroxy aromatic compound having at. least one alkoxy group in at least one of the positions ortho and para to the phenolic hydroxy] group and a hydroxy all- Accordphatic group in which a carbon atom is directly bonded to a carbon atom of the aromatic ring, said compound consisting of carbon, hydrogen and oxygen. s

4. Animal and vegetable fats and oils normally tending to become rancid having incorporated therein, in an amount suflicient to inhibit rancidity development, a monohydroxy aromatic compound of thebenzene series having at least one alkoxy group in at least one of the positions ortho and para to the phenolic hydroxy] group and a hydroxy aliphatic group in which a carbon atom is directly bonded to a carbon atom of the aromatic ring, said compound consisting of carbon, hydrogen and oxygen.

5. Animal and vegetable tats and oils normally tending to become rancid having incorporated therein, in an amount suflicient to inhibit rancidity development, a monohydroxy aromatic compound having an alkoxy group in the position ortho to the phenolic hydroxyl group and a hydroxy aliphatic group in the para position, a carbon atom of the hydroxy aliphatic group being directly bonded to a carbon of the aromatic ring, said compound consisting'of carbon, hydrogen and oxygen.

6. Animal and vegetable fats and oils normally tending to become rancid having incorporated therein, in an amount suflicient to inhibit rancidity development, a monohydroxy aromatic compound of the benezene series having an alkoxy group in the position ortho to the phenolic hydroxyl group and a hydroxy aliphatic group in the para position, a carbon atom of the hydroxy aliphatic group being directly bondedto a carbon of the aromatic ring, said compound consisting of carbon, hydrogen and oxygen.

'7. Edible animal and vegetable fats and oils normally tending to become rancid having incorporated therein, in anamount sufiicient to inhibit rancidity development, a phenol having at least one alkoxy group in an least one of the positions ortho and para to a phenolic hydroxyl group and at least one hydroxy aliphatic group in which at least one carbon atom is directly bonded to a carbon of the aromatic ring, said phenol consisting of carbon, hydrogen and oxygen. 7

8. The method of retarding the development of rancidity in animal and'vegetable fats and oils and compositions containing them which comprises incorporating therein, in an amount suflicient to inhibit rancidity development, a phenol having at least one alkoxygroup in at least one of the positions ortho and para to a phenolic hydroxyl group and at least one hydroxy aliphatic group in which at least one carbon atom is bonded to a carbon of the aromatic ring, said phenol consisting of carbon, hydrogen and oxygen.

9. Animal and vegetable fats and oils normally tending to become rancid havingincorpo: rated therein, in an amount sufllcient to inhibit rancidity development, vanillyl alcohol.

10. Animal and vegetable fats and oils normally tending to become rancid having incorporated therein, in an amount sufficient to inhibit.

rancidity development, coniieryl alcohol.

' GEORGE H. 

